Japanese Patent Application Publication No. 2006-201591 discloses a process unit as an example of the cartridge. The process unit includes a supply roller, a developing roller, a photosensitive drum, and a seal unit. The supply roller is rotatable about its axis and is configured to carry toner as developing agent on its outer peripheral surface. The developing roller is rotatable and in frictional contact with the peripheral surface of the supply roller. The photosensitive drum is rotatable and is in contact with a peripheral surface of the developing roller. The seal unit includes a right and left seal members each in frictional contact with each axial end portion of the developing roller for avoiding toner leakage therefrom. A gap between the right and left seal members is greater than a width of a maximum width sheet conveyed by the photosensitive drum.